Tech Briefs

Researchers work to leverage recent breakthroughs in hearing protection technology.

In the 1988 movie "Good Morning, Vietnam," character Adrian Cronauer, a Saigon- based military disc jockey, performs an on-air skit in which he contacts an artilleryman in the field and offers to play a song for him. "Anything," the artilleryman screams into the phone, "Just play it loud!"

It was a funny line in a popular movie, but for many military veterans— and consequently, for US taxpayers— the noise-induced hearing loss incurred by substantial numbers of US military personnel is no laughing matter. The statistics are staggering. According to a recent Department of Defense (DoD) briefing, "Noise and Military Service: Implications for Hearing Loss and Tinnitus," 75,316 new recipients received Department of Veterans Affairs (VA) compensation for auditory impairments in 2003. Furthermore, the briefing indicates that disabilities of the auditory system (hearing loss and tinnitus, otherwise known as ringing in the ears) were the third most common service-incurred disability, representing 10% of the military's total disabilities in 2003. In 2004, VA costs were $660 million for hearing loss and $190 million for tinnitus, with total expenditures since 1977 topping $6.7 billion in the treatment of injuries related to hearing loss.

ImageAircraft maintainers routinely remove their hearing protection to communicate with others on the flight line or otherwise complete their tasks in a safe manner. While they may be solving their immediate hearing problem, in doing so they are creating a hazardous situation that ultimately contributes to increasing the number of hearing loss victims and the amount of money spent on their treatment. It is a costly, cruel irony that maintainers need to remove their protective headsets in order to hear each other clearly, and therefore function safely, on the flight line. Currently, maintainers wear foam earplugs under their communication headsets—a practice which effectively muffles all external noise, including important communications. Clear ground communications in the highnoise flight line environment are critical both to ensuring the safety of the ground crew and the aircraft pilot and to preventing costly ground-based accidents involving the aircraft.